Safety stop for power engines



F. W. PARSONS. SAFETY STOP FOR POWER ENGINES.

APPLICATION man m4. 6. 1921..

1,41( )9,O2O. I Pafented Mar- 7,1922.

State of New UNITED STAKES PATENT OFFICE.

FREDERICK W. PARSONS, OF ELMIRA, NEW YORK, ASSIGNOR- TO NGERSOLL RANI COMPANY, or JERSEY oI-rY,

NEW JERSEY,

A CORPORATION OF NEW JERSEY.

SAFETY STOP FOR PO'vVER ENGINES.

Application filed January 6, 1921.

T 0 all to 750m it may concern Be it known that I, FREDERICK V. PAR- sons, a citizen of the *nited States, and a resident of Elmira, county of Chemung, York, have invented a certain Safety Stop for Power Engines, of which the following is a specification, accompanied by drawings.

This invention relates to stops for steam actuated compressors or other power engines, and the objects of the invention are to improve upon such automatic stop devices, and secure a simple, efficient and quick acting device which can be relied upon under substantially all conditions of service and will act with certainty upon a predetermined increase of speed of the engine.

To these and'other ends which will hereinafter appear, the invention consists of the automatic safety features of construction, combinations of elements and arrangement tially as hereinafter fully described and claimed in this specification and shown in the accompanying drawings in which- Figure l is a side elevation partly in 1011- of parts substangitudinal section showing so much of a stance the steam end steam engine as will serve to illustrate the invention.

Figure 2 is a top plan view of Figure 1 partly in horizontal section but showing only one longitudinal half of the engine as sufficient to illustrate the invention.

Figure 3 is an enlarged detail vertical sectional view of a portion of the stop device on the line 3-3 of Figure 1 looking in the direction of the arrows, and

Figure 4c is an enlarged detail longitudinal sectional elevation through the inlet valve and inlet chest of the steam cylinder on the line 4l-4E of Figure 2 looking in the direction of the arrows.

Referring to the drawings, so much of a power engine is illustrated as will ser e to show the relation of the different parts forming the engine stop device. In this inof a steam actuated compressor is shown although I am not to be understood as limiting the invention to a stop device for steam engines because the prime mover to which the device is to be applied may be any suitable prime mover.

As shown the steam engine is of the reciprocating type having the bed A, frame B and steam cylinder C together with suit- Specification of Letters Patent.

Patented Mar. '7, 1922. Serial No. 435,430.

able operative reciprocating parts including the cross-head D. The steam cylinder C is provided with the steam inlet E having the hand operated throttle valve F as usual. Between the supply pipe G and the inlet 1 is provided a valve chest H having a yalve seat J upon which the inlet valve K is adapted to seat for automatically stopping the engine upon a predetermined increase of speed. The valve K may be of any suitable construction but for purposes of illustration I have shown the valve pivoted at L on the fork O which is suitablv pinned to the rock shaft P mounted in the walls. of the valve chest H and having alatch arm Q. provided. with the latch It. The latch arm Q may be weighted at S or otherwise arranged to fall when the latch R is released. A latch release lever T pivoted at U to the valve chest H is provided with a keeper V normallv engaging the latch It to hold the latch arm Q in the position indicated in the figures with the controlling valve K open. By rocking the latch release lever T the latch is released and the latch arm Q will fall against the buffer or stop V, thus permitting thecontrolling valve K to close and stopping the engine. I I have shown and described a simple and efficient type of prime mover controlling devi ce but I am not to be understood as limiting the invention to this particular form of mechanism because any suitable controlling devices for stopping the engine may be provided. actuated and controlled by my improved automatic safety engine stop device which includes a movable stop member preferably in the form of a pin X mounted for longitudinal sliding movement on one of the reciprocating parts of the prime mover as for instance, the cross-head D. As shown the pin X may be provided with an enlarged head Y and the shank of the pin extends through the arms a of a bracket Z suitably secured to the cross-head as by means of the bolt 7). The pin is provided with a compression spring 0 held between one of the bracket'arms a and the nuts (Z so that said pin X is normally held in retracted position on the cross-head. The spring 0 should be relatively light and may be adjusted by adjusting the nuts (Z so that the pin is permitted to move or be thrown outwardly in the bracket Z due to its inertia substantially at the instant of reversal of travel of the cross-head D at a predetermined increase of engine speed. In such case, assume that the cross-head is traveling inwardly orto the left as Figure 1 is viewed and as the direction of travel reverses and the cross-head starts to travel outwardly or to the right as Fi ure l is viewed, the inertia of the pin 12 due to its weight and weight of the head Y will serve to carry the pin longitudinally'to the left out of the bracket Z thus compressing the spring 0.

Operative means are provided extending into the path of travel of the pin X and adapted to be struck or pushed by said pin as it moves out of or relatively to the bracket Z on the cross-head D and in this instance I have shown a pivoted lever arm 6 at the lower end of the vertical rod f extending through the guide sleeve 9 suitably secured to the engine frame 6. The upper end of the vertical rod f is provided with the arm 7:. connected by the rod 7' to the latch release lever T. The inner end of the pivoted lever c is adapted to be struck by the head Y of the pin X when said pin moves longitudinally in the bracket Z, in which case the vertical rod 7 is rocked and the keeper V on the latch release lever T is moved away from the latch 1t permitting the latch arm Q to fall and close the controlling valve K, thus stopping the engine.

I claim:

1. In a power engine, a combination of a prime mover and operative reciprocating parts, and an automatic safety engine stop device, including a spring pressed longitudinally movable member slidably mounted on a reciprocating part of the prime mover and adapted to be thrown outwardly due to its inertia'substantially at the instant of reversal of travel of the said reciprocating member upon a given increase of engine speed, and controlling devices for the prime mover controlled by said stop member.

2. In a power engine, the combination of a prime mover and operative reciprocating parts, controlling devices for the prime mover, and an automatic safety engine stop device, including a movable stop member mounted for longitudinal sliding movement on one of the reciprocating parts of the prime mover, and a spring normally holding said movable stop member in retracted position, but permitting the stop member to be thrown outwardly due to its inertia substantially at the instant of reversal of travel of the said reciprocating part on which the stop member is mounted when the engine reaches a predetermined speed, and operative connections actuated by said stop member for adjusting the prime mover controlling devices to stop the engine.

3. In a power engine, the combination with a motive fluid power cylinder and operative driven parts including a reciprocating crosshead, of. a cylinder inlet valve, a latch arm for said valve, a latch release lever co-operating with said latch arm, an automatic safety engine stop device including a movable pin mounted for longitudinal sliding movement on said crosshead, a spring normally holding said pin in retracted position but permitting the pin to be thrown outwardly on the cross-head due to inertia. substantially at the instant of reversal of travel of the cross-head at a predetermined engine. speed, a lever arm extending into the path of movement of the pin and adapted to be struck by the pin at said predetermined engine speed, and operative connections between said lever arm and said latch release lever, whereby the. inlet valve is operated.

4. In a power engine the combination with a motive fluid power cylinder and operative driven parts including a reciprocating crosshead, of a cylinder inlet valve, a rock shaft connected to said valve and having a latch arm, apivoted latch release lever co-operating with said latch arm to hold the valve in normally open position, a bracket on said crosshead, and an automatic safety engine stop device including a movable pin mounted for longitudinal sliding movement in said bracket, and a spring normally holding said pin in retracted position but permitting the pin to be thrown outwardly in the bracket due to its inertia substantially at the instant of reversal of travel of the cross-head at a predetermined increase of engine speed, and a pivoted lever arm extending into the path of movement of said pin and operatively connected to said latch release lever, whereby the pin willbe thrown outward and strike the said lever arm at a predetermined engine speed and release the inlet valve latch to close said valve.

In testimony whereof I have signed this specification.

FREDERICK w. masons. 

